Really all I want is for them to fill in the missing gaps in the player spells that they never got around to or didnt impliment.

I'd love to see for example

WHM get Banishga 3 and Banish 4 which regular mobs have but for whatever reason the Devs never gave players. Maybe add Banish 5 and Banishga 4.
RDM Id like to see get the tier 1 AoE enfeebs since they got tier 2 single having up to Dia 4 and Bio 4 as merit based and Dia 3/Bio 3 as a normal default spell. Maybe Dia and Bio 5 as gifts. Also would like to see the rest of the Poison spells up to tier 5 implimented too.
BLM I'd love to see tier IV aga spells added and maybe have a MAB bonus if the ja spell of the corresponding element was used beforehand. Maybe Tier V aga with gifts.

Theres a bunch of unused spells in the dats that were never implimented wouldbe nice if SE went and used them since theyre there.